iio: accel: adis16209: remove unneeded spi_set_drvdata()

There is no matching spi_get_drvdata() in the driver. This looks like a
left-over from before the driver was converted to device-managed functions.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20201119141806.84827-1-alexandru.ardelean@analog.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/accel/adis16209.c

@@ -279,7 +279,6 @@ static int adis16209_probe(struct spi_device *spi)
 		return -ENOMEM;
 
 	st = iio_priv(indio_dev);
-	spi_set_drvdata(spi, indio_dev);
 
 	indio_dev->name = spi->dev.driver->name;
 	indio_dev->info = &adis16209_info;